Jen Hamel, associate professor in the Department of Biology, has co-authored an article in the current issue of the “” that describes the morphology and calls of two previously undescribed katydid (insect) species endemic to the southern Appalachian Mountains of western NC.

The article, 鈥�,鈥� was co-authored by Hamel, Timothy G. Forrest (first author) of the聽University of North Carolina, Asheville and C. Tate Holbrook of the College of Coastal Georgia. The research was conducted at the University of North Carolina Asheville.

This study reported the results of a study that examined the physical features, calling songs, and duets of two closely related species of katydids. These two species are members of a group of recently diverged and cryptic species, the Amblycorypha rotundifolia聽complex, in which the physical features of each species are very similar, and calling song is the best characteristic for distinguishing among them. In this group of animals, males produce calling songs to attract prospective mates, and females produce short syllables 鈥� 鈥渢icks鈥� 鈥� in precisely timed, duetting responses to the males.

The paper discusses the evolution of signal complexity in this group of animals. Unlike other members of this species complex, males of the two newly described species (Amblycorypha zipticka and A. monticola) each have calling songs with multiple components, or types of syllables. In addition to the other kinds of syllables they produce, males of both species also produce ticks that resemble the tick responses of females, and at the same time intervals when females produce them. Male ticks are hypothesized to be acoustic countermeasures to eavesdropping by other males who are competing for mating opportunities.

Understanding how insect communication is shaped by ecology and evolution is a focus of research in Hamel鈥檚 research group.

The “Journal of Orthoptera Research” is a peer-reviewed, open-access, international journal published by the Orthopterist Society, and its primary focus is to publish studies of the insect order Orthoptera 鈥� the group of insects that includes crickets, katydids, and grasshoppers, and other closely related groups. Its goal is the dissemination of ideas and insights arising from the study of these insects.

The article, 鈥�,鈥� was co-authored by Evora (first author), Rex Cocroft, Shyam Madhusudhan and Hamel. VibePy is a free software solution to a common challenge encountered by researchers who study vibrational communication.

Vibrational communication, in which an animal communicates by shaking or otherwise imparting waves into a substrate, is used by animals ranging from insects to elephants, including an estimated ~200,000 insect species. Researchers often test hypotheses about vibrational communication by using a type of study called a playback experiment. In such experiments, the signals of a focal species are recorded and played to other individuals with the aim of observing their responses to the signals.

A common challenge of vibrational playback experiments is that the substrate through which the signal is played, as well as the hardware used to play the signals, distort the signals via unwanted frequency filtering. An additional challenge is that researchers need to calibrate the amplitude or 鈥渓oudness鈥� of the signals being played, and because propagation of waves through solid substrates is difficult to predict. Therefore, such calibration needs to be done on a case-by-case basis. A software solution that compensates for unwanted frequency filtering and calibrates playback amplitude is available, but it requires a proprietary software license and therefore imposes a cost barrier to researchers.

Research on vibrational communication, or biotremology, is occurring in a diverse and growing community, and Evora and Hamel saw the need for an open-source software solution that could accomplish the same functions as the existing script. They collaborated with Rex Cocroft, a vibrational communication researcher at the University of Missouri who developed the original script, and Shyam Madhusudhana, an animal acoustics researcher with extensive experience developing open-source software for research applications. The tool, VibePy, measures and compensates for undesired filtering and calibrates playback amplitude, and it has been developed using the open-source, cross-platform language Python.

VibePy is available free for download online (doi: 10.5281/zenodo.10059888). The article is part of a themed special journal issue on biotremology. Entomologia Experimentalis et Applicata is a peer-reviewed, international journal published by Wiley, and its primary focus is to publish research in experimental biology and the ecology of insects and terrestrial arthropods. The journal article is being published via open access license, made possible by a publishing agreement between 黑料不打烊 and Wiley.

Evora is currently a research technician in the聽 at Duke University, where she studies early brain development聽using fruit flies as an experimental system. She became interested in the forces that give rise to different animal behaviors while studying vibrational communication in insects at 黑料不打烊. Insect communication and the development of resources to increase research accessibility are active areas of study in .

The article, 鈥淟evels of Airborne Sound And Substrate-borne Vibration Calling Are Negatively Related Across Neotropical False-leaf Katydids,鈥� was co-authored by Hamel, Ciara Kernan (first author), Tony Robillard, Sharon Martinson, Jiajia Dong, Laurel Symes, and Hannah ter Hofstede. The research was conducted at the Smithsonian Tropical Research Institute at Barro Colorado Island in Panama.

This study reported the results of a multi-year study that examined how two types of communication 鈥� airborne sound and substrate-borne vibration 鈥� are used by different but closely related insect species called false-leaf katydids. Both types of signals are used by this subgroup of neotropical katydids to advertise to or attract prospective mates. Why many animal species use more than one modality to communicate is a topic of interest in behavioral and evolutionary ecology.

Here, the authors examined the relative use of airborne sound and substrate-borne vibration by eight different species of katydids from a tropical forest in Panama. They hypothesized that there might be an inverse relationship between signal modalities across species, meaning that if a given species uses sound more, it should use vibration less. They also tested whether any pattern of signaling behavior might be driven by evolutionary relatedness; in other words, if two species that are each others’ closest relatives would both signal most often using the same modality.

The authors found that, across species, there is indeed an inverse relationship between signaling in each modality: katydid species that produce many airborne calls tend to produce few substrate-borne vibrations, and vice-versa. They also found that this pattern was not explained by evolutionary relatedness. They hypothesize that ecological factors such as population density likely outweigh evolutionary history in predicting relative use of each signal type.

Understanding how insect communication is shaped by ecology and evolution is a focus of research in Hamel鈥檚 research group.

Integrative and Comparative Biology is a peer-reviewed, international journal published by Oxford Academic, and its primary focus is to integrate the varying disciplines of organismal biology. It publishes symposia and proceedings from the Society for Integrative and Comparative Biology, as well as聽synthesis, perspectives and empirical articles selected by the editorial board.

The book, “Exploring Animal Behavior Through Sound: Volume 1,” is published through Springer Publishing. The book is written by animal communication researchers and is intended for an upper-level undergraduate audience.

The chapter co-authored by Hamel is titled, “Choosing Equipment for Animal Bioacoustic Research,” and includes conceptual information on working with sound and vibration, as well as constraints, capabilities, and affordability of various types of detection and recording equipment. The chapter covers these topics for the study of sound and vibration through air, water, and solid substrates. Hamel contributed content on the detection and measurement of substrate-borne vibration, a form of communication used by animals ranging from elephants to insects, and an estimated 200,000 species of insects alone.

A PDF of the entire free textbook can be downloaded at:

Carranza presented research on insect behavior and communication at the annual Animal Behavior Society conference held at the Crowne Plaza Corobici Conference Center in San Jos茅, Costa Rica on July 20 through July 23.

Evora presented her Lumen Prize research virtually at the third international Biotremology conference held at the Marine Biology Station in Piran, Slovenia on Sept. 19 through Sept. 22. Hamel co-authored three presentations at Biotremology and led the Charles H. Turner Program, a cohorted undergraduate mentoring program, at the Animal Behavior Society conference.

At the Animal Behavior Society conference, Carranza presented a poster titled, 鈥淓xamining the potential for evolutionary divergence in a plant feeding insect by describing host plant use and vibrational mating signals,鈥� in which she characterized the substrate-borne vibrational signals and host use by a species of plant-feeding insect in the North Carolina Piedmont region. Carranza鈥檚 presentation was recognized by the Animal Behavior Society with the Genesis Award for best undergraduate poster at the conference.

Also at the Animal Behavior Society conference, Hamel led a cohorted undergraduate mentoring program (Charles H. Turner program), which brings 10 to 12 undergraduate and recently graduated students from groups historically underrepresented in science to the annual conference. The program engages the student cohort in a pre-conference orientation workshop, discussions and excursions during the conference, and a virtual peer mentoring group after the conference concludes. Hamel co-chairs the program for the society.

At the Biotremology conference, Alana Evora gave a short oral presentation titled, 鈥淎n open-source tool for conducting high-fidelity vibrational playbacks,鈥� in which she described and demonstrated a software tool developed in the open-source language Python.

The script will facilitate an experimental approach used by many researchers who study vibrational communication in animals. An existing tool used by this research community requires a proprietary software license, imposing an economic barrier on research in this area. The Python script will reduce economic barriers to this type of research. Evora鈥檚 presentation included co-authors Hamel and Rex Cocroft, of the University of Missouri.

Hamel gave an oral presentation titled, 鈥淎 study of multimodal communication using multiple approaches: Uncovering signal functions in a neotropical katydid.鈥澛燭he presentation described the use of acoustic and substrate-borne signals by a focal insect species in the field, as well as findings from experiments in which hypotheses about the signal functions were tested.

The studies in this presentation were conducted by 黑料不打烊 biology alumni Alina Iwan ’19 and Jean Ross ’20, who were both 黑料不打烊 College Fellows. Co-authors included Iwan and Ross, as well as Ciara Kernan, Madilyn Gamble and Hannah ter Hofstede of Dartmouth College. The research was conducted at the Smithsonian Tropical Research Institute on Barro Colorado Island, Panama.

Hamel also co-authored an oral presentation at Biotremology with Ciara Kernan, a doctoral candidate at Dartmouth College; Sharon Martinson, a postdoctoral researcher at Dartmouth; Hannah ter Hofstede, a faculty member at Dartmouth; and Laurel Symes, Assistant Director at the Center for Conservation Bioacoustics at Cornell University. The presentation was titled, 鈥淐omparing airborne and substrate-borne signaling investment across pseudophylline katydids,鈥� and synthesized recent findings by this team about the use of acoustic and vibrational signals by several species of katydids in a comparative evolutionary context.

Work by Hamel and 黑料不打烊 students at Barro Colorado Island has been supported by the 黑料不打烊 Center for Research on Global Engagement, Glen Raven Endowed Fellowships, 黑料不打烊 College Fellows, the College of Arts and Sciences Dean鈥檚 Office, the 黑料不打烊 Undergraduate Research Program and the Acoustical Society of America. Work by Evora on the Python script has been supported by the Lumen and Honors Fellows programs and the Undergraduate Research Program. Work by Carranza on vibrational signaling and host use by a plant-feeding insect has been supported by the 黑料不打烊 Undergraduate Research Program.

The article, 鈥淎 tangled web: Comparing inter-and intraspecific mating dynamics in Anasa squash bugs,鈥� was co-authored by Hamel, Ginny Greenway (first author) and Christine W. Miller of the University of Florida.

This study reported the results of an experiment that examined how mating between individuals of different species occurs and to what degree it affects the reproductive success or the number of offspring produced by a given male or female. Mating between individuals of different species occurs frequently in nature, and understanding the causes and consequences of such mating behavior is a topic of interest in evolutionary ecology.

Here, the authors examined the mating behavior of two closely-related insect species that have been observed mating with each other in the field. By allowing males and females of both species to interact and mate freely under naturalistic conditions, the authors found that 19% of individuals mated with individuals of the 鈥渨rong鈥� different species, but most matings occurred between individuals of the same species.

The authors also measured reproductive success for females of one of the two species. Females who mated with a different-species male produced similar numbers of offspring as those who only mated same-species males. In a previous study, the authors showed that females of this species typically mate with multiple males. It appears that the reproductive costs of occasionally mating with a different-species male are mitigated by also mating with same-species males.

The findings show that in this study system relatively high levels of mating between species likely occurs as a by-product of relaxed pre-copulatory choice by females, a promiscuous mating system and limited reproductive penalties in at least one of the species.

Understanding how mating interactions exert selection on the behavior of insects is a focus of research in Hamel鈥檚 research group.

Journal of Evolutionary Biology is a peer-reviewed, international journal owned by the European Society of Evolutionary Biology and covers micro-and macro-evolution, as well as empirical, computational and theoretical work. It prioritizes articles that make significant advances from a broad conceptual and taxonomic perspective.

The article, 鈥淯ndergraduate research abroad: shared themes in student learning from two models of course-embedded undergraduate research in field biology study abroad courses,鈥� was co-authored by Hamel and Vandermast, along with Hannah ter Hofstede, Adrienne Gauthier and Prudence Merton of Dartmouth College and David Lopatto of Grinnell College. Hamel and Hannah ter Hofstede are joint first authors of the article.

This study describes two upper-level field courses in tropical ecology that travelled in Central America 鈥� one from 黑料不打烊 and one from Dartmouth 鈥� during which students conducted short-term undergraduate research projects. Student learning was evaluated through focus groups, reflective journaling and surveys. Students from both courses reported learning gains unique to conducting undergraduate research in a global context, including curiosity inspired by novel environments and valuing the expertise of local experts for site-specific questions. Students from both courses also reported that their perceptions about who conducts research changed as a consequence of their interactions with the researchers and instructors in the courses.

黑料不打烊 students commented on the positive effects of interactions with host-country individuals, noting that these interactions helped them feel welcome, safe and inspired. Home stays with host families at the beginning of the course also appeared to motivate 黑料不打烊 students to clarify their personal values.

With respect to research, 黑料不打烊 students reported an understanding that it can be a collaborative activity that happens in a community, and they also reported increased confidence about their ability to do research. Six of the eight 黑料不打烊 students sought out additional, post-course research experiences.

Undergraduate research and global learning are both considered to be 鈥渉igh impact practices,鈥� and there is growing interest among academic institutions and researchers in what and how students learn when such practices are combined. Designing courses with two high-impact practices requires consideration of how the design of each high-impact practice may constrain or interact with the other, as well as effects on student learning. Such effects may be parallel, synergistic, or contradictory.

For example, the duration of cultural immersion at each site in a study abroad course is likely to influence the degree of student development in intercultural competence, and the durations of undergraduate research experiences are correlated with student learning gains about research.

Understanding the learning gains associated with course-based undergraduate research is an active area of research for Hamel and Vandermast.

Scholarship and Practice of Undergraduate Research is the official journal of the Council of Undergraduate Research, a national organization of academic institutions that supports the activity of undergraduate research. Funding and support for parts of this study were provided by the 黑料不打烊 Center for the Advancement of Teaching and Learning, and helpful feedback was provided by the 黑料不打烊 Center for Research on Global Engagement Community of Practice.

The article “Exploring the effects of extreme polyandry on estimates of sexual selection and reproductive success” was co-authored by Hamel, Ginny Greenway (first author) and Christine W. Miller of the University of Florida.

This study reported the results of a large experiment that tested how polyandry -when females mate with multiple males – affects reproductive success, or the number of offspring produced by a given male or female. Reproductive success is a key measure for understanding selection, one process by which evolution occurs.

By allowing groups of male and female insects (squash bugs) to interact and mate freely under naturalistic conditions, the authors found that both males and females of this species frequently mate with multiple other individuals. This behavior results in complex networks of mating interactions, rather than the dyads that would be formed by males and females who each only mate with one partner.

The study findings suggest that both males and females appeared to benefit from frequent mating – individuals with more mating partners produced more offspring. Additionally, the order in which females mated with males (and how they used their sperm) greatly influenced estimates of male reproductive success.

The findings show that mating with multiple individuals can have numerous and complex effects on selection, and the study demonstrates that such effects may only be exposed when examined under naturalistic conditions.

Understanding the ways in which mating interactions exert selection on the behavior of insects is a focus of research in Hamel鈥檚 research group.

Behavioral Ecology is the official journal of the International Society for Behavioral Ecology and covers both empirical and theoretical research approaches on the whole range of behaving organisms, including plants, invertebrates, vertebrates, and humans.

The article “” was published in , a disciplinary journal that publishes high-quality original research on animal behavior from theoretical perspectives.

This study reported the results of two experiments conducted as part of Sears’ 黑料不打烊 College Fellows research project. In the first experiment, the authors documented mating durations for a focal insect species. In the second experiment, the authors tested hypotheses to explain the prolonged mating durations that were observed. By manipulating mating durations and then tracking the resulting numbers of eggs and offspring produced by females, the authors evaluated whether prolonged matings benefit female reproductive success.

The study findings suggest that mating durations are highly variable for this species, with first matings lasting eight hours on average, and that females do not benefit from prolonged matings. The data also show that sperm transfer occurs within the first 30鈥塵inutes of copulation, and that females can store viable sperm for up to 4 weeks after a single copulation. The authors suggest that that prolonged matings likely benefit males as a mate-guarding strategy, and that this study species should be a good model organism for studying reproductive conflict.

The results add to the growing literature on reproductive conflict, and they are of interest to researchers studying sexual selection and related topics in behavioral ecology. Successful reproduction is the currency on which selection acts, and the behavior of each individual involved in a copulation may not be adaptive for both. Despite a large number of studies examining reproductive strategies in invertebrates, the discipline is still uncovering general principles, because reproductive behaviors and their outcomes are dynamic and highly variable.

Sears continues to be active in research, and his publications can be viewed on . Topics relating to reproductive conflict are a central area of study in at Lake Forest College. Understanding the ways in which mating behavior affects the ecology and evolution of insects is a focus of research in at 黑料不打烊.

Hamel presented a poster titled, “A comparative study of airborne and vibrational signaling in Neotropical katydids,”聽in which airborne and substrate-borne vibrational signals of six different species of Neotropical katydids were characterized, as well as the relative use of each signal type over 24 hours. Iwan presented a poster titled, 鈥淪tudying the functions and contexts of vibrational communication in Neotropical katydids,鈥� in which Iwan and co-authors described the behavior of one species of Neotropical katydid across four social contexts, with a focus on signaling behavior.

Presentations included co-authors Ciara Kernan, Amber Litterer, Sharon Martinson and Hannah ter Hofstede of Dartmouth College, and Laurel Symes of Cornell University. The posters summarized recent findings by the team from work at the Smithsonian Tropical Research Institute on Barro Colorado Island, Panama. Hamel and her research students have been collaborating with ter Hofstede’s research group to study the behavior and evolution of diversity with this group of insect species.

Work by Hamel and her students at Barro Colorado Island has been supported by the 黑料不打烊 Center for Research on Global Engagement, Glen Raven Endowed Fellowships, 黑料不打烊 College Fellows, the College of Arts and Sciences Dean鈥檚 Office, the Acoustical Society ofAmerica, and the National Geographic / Microsoft Artificial Intelligence for Earth program.

Hamel also co-authored an oral presentation together with Ginny Greenway, a postdoctoral researcher at the University of Florida, and Christine Miller, an Associate Professor at the University of Florida. The presentation was titled, 鈥淗ow does mate assortment influence sexual selection in a highly polyandrous system?鈥� and focused on how the number of times that an individual mates and their number of mating partners influences evolutionary processes.

The team observed and recorded behavior by males and females of a focal insect species in large, semi-natural arenas with a robotic camera system, and they analyzed the resulting dataset with social network analysis. In the focal species, the most promiscuous males mated with less promiscuous females, thus experiencing low levels of sperm competition. Quantifying mating assortment is essential to understanding evolutionary processes associated with mating and mate choice.